Abstract: A pipe cutter includes a housing having a number of teeth formed in the two inner sides. A slide is slidably engaged in the housing and a cutter blade is secured to the slide and to be moved to cut a pipe. A hand grip may be moved toward a handle of the housing for moving the cutter blade forward step by step. A pair of catches are pivotally secured to the slide by pivot pins, and a spring may bias the catches to engage with the teeth of the housing in order to prevent the slide from moving rearward. The housing has two guiding surfaces for disengaging the catches from the teeth and for allowing the slide to be moved backward automatically.